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Stephen A. Watts - One of the best experts on this subject based on the ideXlab platform.
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levels of progesterone testosterone and estradiol and androstenedione metabolism in the Gonads of lytechinus variegatus echinodermata echinoidea
Comparative Biochemistry and Physiology Part C: Pharmacology Toxicology and Endocrinology, 2000Co-Authors: Kristina M. Wasson, Barbara A. Gower, Gene A. Hines, Stephen A. WattsAbstract:Levels of progesterone (P4), testosterone (T) and estradiol (E2) indicated significant variation among individual echinoids during the annual cycle, reflecting generally the variation in gamete development that can be observed among individuals. Testosterone and E2 levels in both the ovaries and testes were higher during the period of Gonadal growth. Levels of all steroids were greatly reduced compared to those levels reported for asteroids. Differences in the levels of P4, T, and estrogens between asteroids and Lytechinus variegatus may be related to differences in Gonad morphology and nutrient storage capacity between asteroids and echinoids. It was hypothesized that the low levels of steroids detected in L. variegatus reflect paracrine-like mechanisms in cell signaling as compared to endocrine-like mechanisms proposed to be involved in regulating Gonad Function in asteroids. Both the ovaries and testes of L. variegatus had the capacity to synthesize T and a variety of 5alpha-reduced androgens including 5alpha-androstane-3beta,17beta-diol and 5alpha-androstane-3alpha,17beta-diol (5alpha-adiols) from androstenedione (AD) in 8 h. Estrogen synthesis was not detected. The sex-specific pattern of accumulation of 5alpha-adiols in the ovaries and testes suggests that the 5alpha-adiols may affect processes related to reproduction in L. variegatus.
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Levels of progesterone, testosterone, and estradiol, and androstenedione metabolism in the Gonads of Lytechinus variegatus (Echinodermata:echinoidea).
Comparative Biochemistry and Physiology Part C: Pharmacology Toxicology and Endocrinology, 2000Co-Authors: Kristina M. Wasson, Barbara A. Gower, Gene A. Hines, Stephen A. WattsAbstract:Abstract Levels of progesterone (P4), testosterone (T) and estradiol (E2) indicated significant variation among individual echinoids during the annual cycle, reflecting generally the variation in gamete development that can be observed among individuals. Testosterone and E2 levels in both the ovaries and testes were higher during the period of Gonadal growth. Levels of all steroids were greatly reduced compared to those levels reported for asteroids. Differences in the levels of P4, T, and estrogens between asteroids and Lytechinus variegatus may be related to differences in Gonad morphology and nutrient storage capacity between asteroids and echinoids. It was hypothesized that the low levels of steroids detected in L. variegatus reflect paracrine-like mechanisms in cell signaling as compared to endocrine-like mechanisms proposed to be involved in regulating Gonad Function in asteroids. Both the ovaries and testes of L. variegatus had the capacity to synthesize T and a variety of 5α-reduced androgens including 5α-androstane-3β,17β-diol and 5α-androstane-3α,17β-diol (5α-adiols) from androstenedione (AD) in 8 h. Estrogen synthesis was not detected. The sex-specific pattern of accumulation of 5α-adiols in the ovaries and testes suggests that the 5α-adiols may affect processes related to reproduction in L. variegatus .
Alberto Contri - One of the best experts on this subject based on the ideXlab platform.
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Pulse wave Doppler ultrasound of testicular arteries and their relationship with semen characteristics in healthy bulls
BMC, 2018Co-Authors: Alessia Gloria, Domenico Robbe, Augusto Carluccio, Laura Wegher, Claudio Valorz, Alberto ContriAbstract:Abstract Background Semen evaluation is used to estimate the testicular Function. In bulls, the spermatozoa present in the ejaculate are the result of a process that begun more than 2 mo earlier, bequeathing a delayed depiction of the actual Function of the testis. Since testis vascularization might be critical for the Gonad Function, selected pulse wave Doppler ultrasound parameters were assessed in this study, for instance the peak systolic velocity, the end diastolic velocity and the resistive index of the testicular artery along the spermatic cord, the marginal portion of the testicular artery and the intratesticular branches of the testicular artery both in healthy adult and young bulls. Correlations between these parameters and characteristics of semen that was collected numerous times, before and after the Doppler ultrasound examination. Results The peak systolic velocity and the end diastolic velocity measured in the testicular artery along the spermatic cord (supratesticular artery – SA) were variable among the bulls and within individual bulls, likely due to the convoluted course of the vessel. The resistive index was found highly repeatable in the same bull. A reduction in the resistive index was found between the supratesticular artery and the marginal portion of the testicular artery (P
Contri Alberto - One of the best experts on this subject based on the ideXlab platform.
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Pulse wave Doppler ultrasound of testicular arteries and their relationship with semen characteristics in healthy bulls
'Springer Science and Business Media LLC', 2018Co-Authors: Gloria Alessia, Carluccio Augusto, Wegher Laura, Robbe Domenico, Valorz Claudio, Contri AlbertoAbstract:Background: Semen evaluation is used to estimate the testicular Function. In bulls, the spermatozoa present in the ejaculate are the result of a process that begun more than 2 mo earlier, bequeathing a delayed depiction of the actual Function of the testis. Since testis vascularization might be critical for the Gonad Function, selected pulse wave Doppler ultrasound parameters were assessed in this study, for instance the peak systolic velocity, the end diastolic velocity and the resistive index of the testicular artery along the spermatic cord, the marginal portion of the testicular artery and the intratesticular branches of the testicular artery both in healthy adult and young bulls. Correlations between these parameters and characteristics of semen that was collected numerous times, before and after the Doppler ultrasound examination. Results: The peak systolic velocity and the end diastolic velocity measured in the testicular artery along the spermatic cord (supratesticular artery - SA) were variable among the bulls and within individual bulls, likely due to the convoluted course of the vessel. The resistive index was found highly repeatable in the same bull. A reduction in the resistive index was found between the supratesticular artery and the marginal portion of the testicular artery (P < 0.01), and between the marginal portion of the testicular artery and the intratesticular branches of the testicular artery (P < 0.05). No differences were recorded for the pulse wave Doppler ultrasound parameters in young bulls compared with adults. A significant correlation was found between the resistive index of the marginal portion of the testicular artery and total sperm in the ejaculate (r = 0.516, P < 0.05), the immature sperm (r = 0.462, P < 0.05), the teratoid sperm (r = 0.375, P < 0.05), and the "Dag defect" sperm (r = 0.389, P < 0.05). Similarly, the resistive index of the intratesticular branches of the testicular artery were found correlated with the total sperm number in the ejaculate (r = 0.568, P < 0.05), the immature sperm (r = 0.523, P < 0.05), the teratoid sperm (r = 0.418, P < 0.05), and the "Dag defect" sperm (r = 0.341, P < 0.05). Conclusions: The data presented in this study suggest that the resistive index, measured at the marginal portion of the testicular artery, could be an easy-to-perform parameter to evaluate the spermatogenesis quality in young bulls and normal adults
Gunna Tof - One of the best experts on this subject based on the ideXlab platform.
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amniotic fluid phthalate levels and male fetal Gonad Function
Epidemiology, 2015Co-Authors: Morten Sondergaard Jense, Ravinde Anandivell, E Norgaardpederse, O Jonsso, Jens Pete Onde, David M Hougaard, Arieh Cohe, Christia H Lindh, Richard Ivell, Gunna TofAbstract:Prenatal exposure to phthalates may pose a threat to human male reproduction. However, additional knowledge about the in vivo effect in humans is needed, and reported associations with genital abnormalities are inconclusive. We aimed to study prenatal di(2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DiNP) exposure in relation to cryptorchidism, hypospadias, and human fetal Leydig cell Function.
Kristina M. Wasson - One of the best experts on this subject based on the ideXlab platform.
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levels of progesterone testosterone and estradiol and androstenedione metabolism in the Gonads of lytechinus variegatus echinodermata echinoidea
Comparative Biochemistry and Physiology Part C: Pharmacology Toxicology and Endocrinology, 2000Co-Authors: Kristina M. Wasson, Barbara A. Gower, Gene A. Hines, Stephen A. WattsAbstract:Levels of progesterone (P4), testosterone (T) and estradiol (E2) indicated significant variation among individual echinoids during the annual cycle, reflecting generally the variation in gamete development that can be observed among individuals. Testosterone and E2 levels in both the ovaries and testes were higher during the period of Gonadal growth. Levels of all steroids were greatly reduced compared to those levels reported for asteroids. Differences in the levels of P4, T, and estrogens between asteroids and Lytechinus variegatus may be related to differences in Gonad morphology and nutrient storage capacity between asteroids and echinoids. It was hypothesized that the low levels of steroids detected in L. variegatus reflect paracrine-like mechanisms in cell signaling as compared to endocrine-like mechanisms proposed to be involved in regulating Gonad Function in asteroids. Both the ovaries and testes of L. variegatus had the capacity to synthesize T and a variety of 5alpha-reduced androgens including 5alpha-androstane-3beta,17beta-diol and 5alpha-androstane-3alpha,17beta-diol (5alpha-adiols) from androstenedione (AD) in 8 h. Estrogen synthesis was not detected. The sex-specific pattern of accumulation of 5alpha-adiols in the ovaries and testes suggests that the 5alpha-adiols may affect processes related to reproduction in L. variegatus.
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Levels of progesterone, testosterone, and estradiol, and androstenedione metabolism in the Gonads of Lytechinus variegatus (Echinodermata:echinoidea).
Comparative Biochemistry and Physiology Part C: Pharmacology Toxicology and Endocrinology, 2000Co-Authors: Kristina M. Wasson, Barbara A. Gower, Gene A. Hines, Stephen A. WattsAbstract:Abstract Levels of progesterone (P4), testosterone (T) and estradiol (E2) indicated significant variation among individual echinoids during the annual cycle, reflecting generally the variation in gamete development that can be observed among individuals. Testosterone and E2 levels in both the ovaries and testes were higher during the period of Gonadal growth. Levels of all steroids were greatly reduced compared to those levels reported for asteroids. Differences in the levels of P4, T, and estrogens between asteroids and Lytechinus variegatus may be related to differences in Gonad morphology and nutrient storage capacity between asteroids and echinoids. It was hypothesized that the low levels of steroids detected in L. variegatus reflect paracrine-like mechanisms in cell signaling as compared to endocrine-like mechanisms proposed to be involved in regulating Gonad Function in asteroids. Both the ovaries and testes of L. variegatus had the capacity to synthesize T and a variety of 5α-reduced androgens including 5α-androstane-3β,17β-diol and 5α-androstane-3α,17β-diol (5α-adiols) from androstenedione (AD) in 8 h. Estrogen synthesis was not detected. The sex-specific pattern of accumulation of 5α-adiols in the ovaries and testes suggests that the 5α-adiols may affect processes related to reproduction in L. variegatus .